Epigenetic regulation of stem cells and development by the DNA dioxygenase Tet2

DNA 双加氧酶 Tet2 对干细胞和发育的表观遗传调控

基本信息

批准号：
10348168
负责人：
Julio C Flores
金额：
$ 5.18万
依托单位：
ALBERT EINSTEIN COLLEGE OF MEDICINE
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-01-01 至 2023-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10348168
关键词：
Affect Binding Biological Biological Assay Biology Cell Differentiation process Cell Lineage ChIP-seq Chimera organism Chromatin Chromatin Remodeling Factor Chromosome Mapping Complex DNA DNA Methylation Data Defect Deposition Development Dioxygenases Disease Embryonic Development Enhancers Enzymes Epigenetic Process Family Family member Gene Activation Gene Expression Gene Expression Regulation Genes Genetic Transcription Genomics Goals HDAC2 gene Health Hematologic Neoplasms Hematopoietic Hematopoietic System Histones Human Hydroxylation In Vitro Knock-out Knockout Mice Knowledge Lead Light Link Literature Malignant Neoplasms Malignant lymphoid neoplasm Maps Measures Mediating Mentorship Mus Mutate Myelogenous Myeloproliferative disease N-Acetylglucosaminyltransferases Nervous system structure Neurodegenerative Disorders Nucleic Acid Regulatory Sequences Oxides Physicians Plant Roots Process Proteins Regenerative Medicine Regulator Genes Regulatory Element Research Research Personnel Research Training Role Scientist Stem Cell Development Structure Testing Tetanus Helper Peptide UDP-N-acetylglucosamine-peptide beta-N-acetylglucosaminyltransferase bisulfite sequencing defined contribution demethylation embryonic stem cell epigenetic regulation experimental study fetal gene repression histone deacetylase 2 histone modification human disease induced pluripotent stem cell leukemia mutant novel programs promoter recruit regenerative therapy relating to nervous system skills stem cell biology stem cell differentiation stem cell genes stem cells transcriptome transcriptome sequencing transcriptomics

项目摘要

ABSTRACT The Ten-eleven translocation (Tet1/2/3) family of enzymes are epigenetic regulators of gene expression important for stem cell biology and embryonic development. Tet enzymes are dioxygenases that promote DNA demethylation by converting 5-methylcytosine (5mC) into 5-hydroxymethycytosine (5hmC) and higher oxidized derivatives. In addition to this enzymatic activity, Tet enzymes can bind chromatin modifying complexes, to regulate genes in a presumably catalytic-independent manner. Tet2 is a key member of this family. It is highly expressed in embryonic stem cells (ESCs) and controls gene expression programs necessary for stem cell lineage specification. Tet2 is also frequently mutated in hematological malignancies and has been implicated in neurodegenerative diseases. While the catalytic functions of Tet2 have been well studied, its non-catalytic roles remain poorly defined. In this proposal, we seek to establish the significance of the catalytic dependent and independent functions of Tet2 in ESC gene regulation and lineage commitment. We hypothesize that Tet2, in addition to regulating genes through its DNA demethylase activity, can also modulate genes in a non-catalytic fashion by recruiting histone modifiers to the chromatin, and this dual mode of gene regulation is essential for proper ESC differentiation along the neural and hematopoietic lineages. To test this hypothesis, I have generated Tet2 catalytic mutant (Tet2m/m) and knock-out (Tet2–/–) ESCs, which I will use as a platform to: (1) identify the catalytic and non-catalytic direct target genes of Tet2 in ESCs by integrating changes in gene expression with Tet2 genomic occupancy, (2) establish Tet2-mediated activating and repressing mechanisms of gene regulation involving interactions with histone modifiers OGT and HDAC2, and finally (3) define the biological significance of Tet2 enzymatic and non-enzymatic functions in ESC differentiation and lineage commitment along the neural and hematopoietic lineages. Findings from these experiments will elucidate novel epigenetic mechanisms of gene regulation in ESCs involving Tet2 catalytic and non-catalytic functions. They will enhance our understanding of stem cell biology and development and can have implications in hematological malignancies where Tet2 is affected. Under the combined mentorship of Drs. Meelad Dawlaty and Bernice Morrow, I will successfully execute the proposed research and training plans. This will allow me to contribute greatly to the fields of epigenetics and stem cell biology and develop the necessary research, professional and interpersonal skills to become and independent physician-scientist investigator.

抽象的十十一易位 (Tet1/2/3) 酶家族是基因表达的表观遗传调节因子 Tet 酶对干细胞生物学和胚胎发育很重要，是促进 DNA 的双加氧酶。通过将 5-甲基胞嘧啶 (5mC) 转化为 5-羟甲基胞嘧啶 (5hmC) 和更高的氧化程度进行去甲基化除了这种酶活性外，Tet 酶还可以结合染色质修饰复合物。 Tet2 是该家族的一个关键成员，它以一种不依赖于催化的方式调节基因。在胚胎干细胞 (ESC) 中表达并控制干细胞必需的基因表达程序 Tet2 在血液系统恶性肿瘤中也经常发生突变，并与多种疾病有关。虽然 Tet2 的催化功能已得到充分研究，但其非催化作用。在本提案中，我们试图确定催化依赖性和催化依赖性的重要性。 Tet2 在 ESC 基因调控和谱系定型中的独立功能除了通过其 DNA 去甲基化酶活性调节基因外，还可以以非催化方式调节基因通过将组蛋白修饰剂招募到染色质来时尚，这种基因调控的双重模式对于为了验证这一假设，我提出了 ESC 沿神经和造血谱系的正确分化。 Tet2 催化突变体 (Tet2m/m) 和敲除型 (Tet2–/–) ESC，我将使用它们作为平台来：(1) 识别通过整合基因表达的变化，研究ESC中Tet2的催化和非催化直接靶基因 Tet2基因组占据，(2)建立Tet2介导的基因调控激活和抑制机制涉及组蛋白修饰剂 OGT 和 HDAC2 的相互作用，最后 (3) 定义生物学意义 Tet2 酶促和非酶促功能在 ESC 分化和沿神经细胞谱系定型中的作用这些实验的结果将阐明新的表观遗传机制。 ESC 中涉及 Tet2 催化和非催化功能的基因调控将增强我们的功能。了解干细胞生物学和发育，并对血液恶性肿瘤产生影响在 Meelad Dawlaty 和 Bernice Morrow 博士的共同指导下，我将在 Tet2 受到影响的地方进行研究。成功执行拟议的研究和培训计划将使我能够为该项目做出巨大贡献。表观遗传学和干细胞生物学领域，并发展必要的研究、专业和人际关系成为独立的医师科学家研究者的技能。